Illuminated toggle switch



June 27, 1950 SHERRARD 2,512,975

ILLUMINATED TOGGLE SWITCH Filed Aug. 14, 1947 2 Sheets-Sheet l BY WTTORNEY.

June 27, 1950 E. W. SHERRARD ILLUMINATED TOGGLE SWITCH Filed Aug. 14,1947 r, 72 EM 5% @7 2 Sheets-Sheet 2 INVENTOR.

27m W .f/rerrard ATTORNEY.

Patented June 27, 1950 UNITED STATES PATENT OFFICE 13 Claims.

The present invention relates in general to electrical switches and itdeals more particularly with toggle switches of the type mounting flushwith the wall and having an operating lever or handle projectingoutwardly therefrom for the purpose of turning the switch on or off.

An important object of the invention is to provide an improvedarrangement for artificially illuminating the exposed part of theoperating lever or handle so that no difliculty will be experienced inlocating same in the dark. I am aware that in the past miniatureelectric lamps have been placed within the movable operating handleitself in some cases for this purpose, but such arrangements areexpensive, complicated and subject to early failure due to themechanical difiiculty of supplying energizing current to the movablelight. Moreover, being exposed to the direct view, lamps thus mountedgive a harsh light and because of their general unattractiveness are notacceptable from a decorative standpoint in many places.

Broadly speaking, it is the object of the present invention to provide atoggle switch which is free of all of these shortcomings, the operatinghandle being attractively lighted from a source which is inconspicuousand which nowise interferes with or complicates the switch mechanism. Tothis end an operating lever or handle of lightconducting material isemployed together with a diminutive lamp stationarily mounted within theswitch housing adjacent the rear of the handle but out of the directline of view whereby light permeates the movable handle bytransillumination.

According to one feature of the invention the handle may be transparent,translucent or it may have embedded or distributed therein materialwhich is adapted to fluoresce under the influence of the lamp.

Another feature resides in the manner of locating the lamp whereby it ismost favorably positioned for illuminating the handle when the latter isin "off" or circuit-opening position.

A further object of the invention is to provide an arrangementfacilitating replacement of the lamp employed to illuminate a toggleswitch handle from the rear.

Another object is to providea lamp for not dle from the rear but alsoilluminating a stationary target or name plate bearing a printed legendor other indicia. Another feature resides in the manner in which such aname plate is edge lighted.

Still another object is to provide a single source of light forilluminating the toggle switch handle and also casting a beam of lightin anydesired direction in respect thereto. A further feature resides inthe provision of circuit means for altering the intensity of the light.

Other objects and features will appear in the course of the followingdescription of the invention.

In the accompanying drawings which-form a part of the specification andare to be read in conjunction therewith and in which like referencenumerals are employed to indicate like parts of the various views,

Fig. 1 is a front elevation of a preferred embodiment of my toggleswitch together with the escutcheon or switch plate associatedtherewith, showing the assembly as it appears when mounted on the wall,

Fig, 2 is a side elevation of the toggle switch unit properly drawn to alarger scale,

Fig. 3 is a front elevation of the toggle switch unit,

Fig. 4 is a cross sectional view taken substantially along: the line 4-4of Fig. 3 in the direction of the arrows,

Fig. 5 is a front elevation of a gang of switches employing analternative form of construction,

Fig. 6 is a side elevation of one of the switches in Fig. 5 and theassociated mounting plate,

Fig. '7 is an enlarged cross section taken along the line 1-1 of Fig. 5in the direction of the arrows,

Fig. 8 is a fragmentary cross section taken along the line 88 of Fig. '7in the direction of the arrows,

Fig. 9 is a front elevation of another alternative form of switchstructure,

Fig. 10 is an enlarged cross section taken along the line Ill-I0 of Fig.9 in the direction of the arrows,

Fig. 11 is a schematic diagram of a circuit employing the switch ofFigs. 9 and 10,

Fig. 12 is a front elevation of still another switch structure embodyingthe invention, and

Fig. 13 is an enlarged fragmentary cross section taken along the line|3-|3 of Fig. 12.

Referring first to Figs. 2, 3 and 4, these illustrate a toggle switchunit of the type having an operating handle or lever l extendingoutwardly through an aperture IS in the front of a housing H. The handleis adapted to pivot about a horizontal axis located inside the housingwhereby it can be displaced manually from the position illustrated inFig. 4 to the position a suitable support, the specific mountingarrangement and cover holding device being of no consequence, however,in so far as the present invention is concerned.

Inside the housing there are two stationary contacts 23 and 24 eachcomprising a. pair of spring members engaging opposite faces of aninsulating wafer 25. The upper contact is carried by a terminal 26 andthe lower contact by terminal 21, each terminal having a screw 28 bymeans of which the external circuit of the switch is connected to thatterminal. Wafer 25 carries a metallic strip 29 adapted to occupy theposition shown when handle I5 is down; when the handle is moved up toits dotted position, however, the wafer turns in a cloclewise directionabout pivot 3| in order to bring the opposite ends of strip 29 under thestationary wiping contacts 23 and 24 respectively and thus completes acircuit between terminals 26 and 21. The mechanism by which this is doneforms no part of the present invention and hence has not been shown indetail. As conventional, it comprises a snap-acting, over-center togglelinkage between lever l5 and wafer 25 such that the wafer remainsstationary during app oximately the first half of the levers movement ineither direction and then snalps very rapidly to its opposite positionas the level passes dead center.

Above the switch mechanism in the housing is a diminutive lamp 32 whichmay be of the incandescent filament type but preferably is of the typefilled with a gas (such as neon) adapted to glow gently when ionized bythe potential connected to its terminals. The lamp is disposed crosswiseof the housing with its base in a hole 33 in one side wall thereof. Itwill be observed that this side wall is made thicker than the oppositewall and it contains grooves or channels 34 and 35 extending from hole33 to terminals 26 and 21 respectively. One terminal of lamp 32 isconnected to switch terminal 26 by means of a pigtail wire disposed inthe upper groove; in the lower groove is a resistor 36, one end of whichis connected to switch terminal 21 and the other end of which isconnected to the second terminal of the lamp. After the parts have beenthus connected, the grooves preferably are filled with sealing wax orother suitable insulating material.

From the above it will be clear that lamp 32 and resistor 36 areconnected in series between switch terminals 26 and 21 whereby the lampwill glow when the switch is open (i. e., as shown in Fig. 4) due to thepotential connected to the switch terminals over the external switchcircuit. Should this potential be removed, for example due to a fault orfailure of equipment in the external circuit, the lamp will beextinguished and hence given warning of the trouble.

Handle I5 may be made of clear or colored transparent material so thatthe light impinging upon its rear portion will proceed through the bodyof the handle to the forwardmost extremity thereof. Alternatively, thehandle may be translucent or it may have molded therein a material whichfluoresces under the influence of the ultraviolet rays emitted by lamp32 along with visible light (assuming the lamp tobe of the ionized gastype). In any of these cases when the switch is mounted for use with aconventional opaque switch plate or escutcheon 38 as shown in Fig. l thelighted operating handle makes it possible to locate the switch easilyin the darkest room for purposes of closing the switch. When the switchis closed the external circuit will be rendered operative by virtue ofcontacts 26 and 21 being bridged by metallic strip 29; this strip alsoserves under these circumstances to short circuit resistor 36 and lamp32 so that lamp 32 is ex tinguished.

By positioning lamp 32 as shown it has been found virtually impossibleto see the lamp itself from the front of the switch even when a cleartransparent handle is employed; nevertheless due to the transilluminative effect achieved by thus positioning the lamp with respect tothe handle the glow of the handle may be seen easily from alldirections. If desired, all or any selected area of the protrudingportion of the handle may be etched or sandblasted to enhance itslight-gathering characteristic or to obtain special decorative efiects.

Turning to Figs. 5 to 8, inclusive, the switch unit shown therein isessentially like the one already described except for the manner inwhich the handle-illuminating lamp is arranged.

Above the switch housing proper and preferably integral therewith is a,generally tubular auxiliary housing 40 adapted to receive the lamp 4|.The forward end of the auxiliary housing is threaded to receive a. cap42 and over the rear end of the housing is contact spring 43 againstwhich the lamp's central terminal is urged when the cap is in place. Thelatter contact spring connects to the upper switch terminal 44 as shown.The other lamp terminal is an annular collar 45 which is engaged bothtop and bottom by a contact spring 46 as best seen in Figs. 7 and 8.Spring 46 in turn is conected to the upper end of a resistor 41 disposedin groove 48, the other end of the resistor being connected to the lowerswitch terminal 43.

Thus lamp 4| and resistor 41 are connected in series between the twoswitch terminals, and they function circuitwise in the same fashion asthe arrangement shown in Figs. 1 to 4, which is to say that the lampwill be lighted when switch handle 50 is in the position shown. Undersuch circumstances the light passes downwardly through the aperture 5|illuminating the switch handle as hereinbefore described.

Although somewhat more expensive to manufacture the arrangement of Figs.5 to 8 has certain advantages over the structure of Figs. 1 to 4. In thefirst place the lamp 4| may easily and quickly be replaced when it burnsout simply by unscrewing cap 42 to permit withdrawal of the lamp throughthe upper aperture in face plate 52. To facilitate screwing and'unscrewing cap 42 it may be provided as shown with a slot adapted toreceive a screw-driver or the edge of coin; alternatively, the slot maybe omitted and the cap provided with a knurled rim to permit it to begripped easily.

If desired cap 42 may be of opaque material matching switch plate 52 butpreferably it is molded of transparent or translucent material bearing aletter, legend or other characterizing mark identifying the circuitcontrolled by the associated switch. This is particularly useful whereseveral switches are mounted together in Z a gang arrangement asillustrated in Fig. 5.

Turning now to Figs. 9 and 10, these show a handle-lighting lamp 55mounted in a lamp housing 66 similar to the one just described. Insteadof a screw-on cap for the front of the housing, however, there isprovided a rotatable cylindrical lens 51 held in place by a ring 68occupying registering opposed annular grooves in the lens and housing.The projecting forward portion of the lens has a flat surface 69parallel to the axis of rotation of the lens and an inclined prismaticsurface 60 serving to reflect the light from the lamp 55 through surfaceas indicated by the arrows in Fig. 10. An identifying mark or legendengraved or etched either on the reflecting surface 60 or thetransmitting surface 59 will be plainly visible from above when lens 61occupies the position shown, or from one side of the switch if the lensis rotated 90 about its axis. Regardless of the position of the lens,light shining downwardly through aperture 6| will illuminate handle 62as previously described.

The switch shown in Fig. is a single-pole, double-throw switch having aneutral intermediate position and it is intended for the control of,say, an audible signal such as a door bell or buzzer. It has threestationary contacts 63, 64, and 65 and a movable contact 66 adapted topivot at 61 as handle 62 is moved up or down. Bridging member 68 on themovable contact connects the center contact 64 to the upper contact 63when the handle is pushed down and connects the center contact to thelower contact 66 when the handle is pushed up. Springs 69 restore themovable contact to the neutral center position when pressure is removedfrom handle 62.

The preferred door buzzer and lamp circuit is shown schematically inFig. 11. Assuming the switch to be in its center position as shown, itwill be seen that alternating current passing through the step-downtransformer ID will energize the series circuit comprising the secondarywinding of the transformer, buzzer II, lamp 55 and resistor 12. Thetotal resistance in this circuit is such as to maintain the current at acomparatively low value whereby buzzer II will not operate but lamp 55will glow gently. Thus the handle 62 of the switch and the prism 51 willbe illuminated. If the handle now is depressed, bridging member 66 willshort circuit resistor 12 and lamp 55 and hence connect full voltage ofthe transformer secondary winding to the buzzer rendering the latteroperative. On the other hand, if the handle is raised, bridging member68 will short circuit a portion of resistor 12 thus increasing thecurrent through lamp 66 and buzzer H, but not enough to render thebuzzer operative.

This increase in current increases the intensity of light given oil bylamp 55 which naturally increases the illumination of the switch handleand prism 51. More important, the light reflected by the prism underthese circumstances forms a directed beam capable of brightlyilluminating nearby objects such, for example, as a keyhole ll disposedin the vicinity of the buzzer switch. The keyhole may be on either sideor above the switch, it only being necessary to turn the prism about itsaxis in order to direct the beam in the proper direction.

Another modification employing the same basic form of switch mechanismis shown in Figs. 12 and 13. In this structure a transparent name plate15 is fastened to the front switch plate so that the recess 16 in therear of the name plate receives the tip of lamp l1. Lamp 11, therefore,not only illuminates the switch handle I6 through aperture 19 but alsotransmits its light throughout the body of the name plate. An opaquecoating or insert is placed in recess 16 opposite the end of the lamp tohide the lamp from direct view, the illumination of the name plate beingsolely the result of light passing from the lamp radial to its axis intothe plate through the circumferential edge of recess 16. A name, legendor decorative design engraved or etched on the plate will catch thelight thus transmitted and stand out prominently in an easily visibleand attractive manner.

From the foregoing it will be seen that this invention is one welladapted to attain all of the ends and objects hereinbefore set forthtogether with other advantages which are obvious and which are inherentto the apparatus.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

. Inasmuch as many possible embodiments of the invention may be madewithout departing from the scope thereof, it is to be understood thatall matter herein set forth or shown in the accompanying drawings is tobe interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. A toggle switch for opening and closing electrical circuits,comprising an opaque housing having top, bottom and side wallscompletely enclosing the space within the housing, a switch-operatinglever mounted to pivot about an axis inside the housing, the free end ofsaid lever projecting through an aperture in one wall of the housing,means for artificially illuminating the entire interior of said housingand the inner end of said lever, said means comprising an elongated lampfixedly mounted in the housing with its axis parallel to the axis aboutwhich said lever pivots, said lamp being offset laterally from saidlever and positioned beside said aperture substantially against theinside of said one wall, and said lever being of light-transmittingmaterial' whereby the light from said lamp passes therethrough and isvisible outside said housing.

2. A toggle switch for opening and closing electrical circuits,comprising an opaque housing, a switch-operating lever mounted to pivotabout an axis inside the housing, the free end of said lever projectingthrough an aperture in one wall of the housing, a secondaperture in saidone wall of the housing, said housing including a stationary socketbehind said second aperture, an electric lamp removably-mounted in thesocket and adapted to shine on the part of said lever inside thehousing, said lever being of light-transmitting material whereby thelight from said lamp reaches outside the housing, and a removableclosure for said second aperture.

3. A toggle switch as in claim 2 wherein said removable closure is alight-transmitting body with indicia thereon. 4. A switch as in claim 2wherein said removable closure comprises a transparent plate having arecess in one face adapted to receive a portion of the electric lamp, anopaque shield in the bottom of the recess whereby light passes into theplate only through the side walls of the recess.

5. A toggle switch for opening and closing electrical circuits,comprising a switch housing,- a switch-operatinglever mounted to pivotabout an axis inside the housing, the free end of said lever projectingthrough an aperture in one wall of the housing, a second aperture insaid one wall of the housing, said housing including a stationary socketbehind said second aperture, an electric lamp removably mounted in thesocket and adapted to shine on the part of said lever inside thehousing, said lever being of light-transmitting material whereby thelight from said lamp reaches outside the housing, and a rotatableclosure for said aperture, said closure comprising a prism having oneface parallel to the axis of rotation of the closure and another faceoblique to said axis.

6. A toggle switch for opening and closing electrical circuits,comprising a switch housing, a switch-operating lever mounted to pivotabout an axis inside the housing, the free end of said lever projectingthrough an aperture in one wall of the housing, a tubular lamp housingadjacent the switch housing with its axis transverse to the axis aboutwhich said lever pivots, an elongated lamp in the lamp housing, acontact spring over one end of the lamp housing engaging the end of thelamp and a removable closure over the other end of the housing engagingthe opposite end of the lamp, an aperture between the two housingsthrough which light from said lamp is adapted to shine on the part ofsaid lever inside the switch housing, said lever being oflight-transmitting material whereby light from said lamp reaches outsidethe housing.

7. A toggle switch for opening and closing electrical circuitscomprising an opaque housing having front and side walls, a switchoperating lever mounted to pivot about an axis inside the housing, thefree end of said lever projecting through an aperture in the front wallin the housing, an elongated tubular lamp projecting into said housingthrough an aperture in one side wall of the housing, said last apertureclosely encircling the lamp whereby the lamp is supported in and by saidone side wall, said last aperture being so positioned in the side wallthat the portion of the lamp inside the housing is disposed beside theaperture in the front wall and substantially against the inside of thefront wall of the housing, and said lever being of light transmittingmaterial whereby the light from said lamp passes through the lever tothe free end thereof.

8. A toggle switch for opening and closing electrical circuitscomprising an opaque housing having front and side walls, a switchoperating lever mounted to pivot about an axis inside the housing, thefree end of said lever projecting through an aperture in the front wallin the housing, an elongated tubular lamp projecting into said housingthrough an aperture in one side wall of the housing, said one side wallbeing of appreciable thickness and said aperture therein conformingclosely in size to the cross section of said lamp thereby to preventcanting of the lamp, pigtafl terminals on the lamp outside the housingand anchored to the housing to prevent axial move-' ment of the lamp insaid last aperture. said last aperture being so positioned in the sidewall that the portion of the lamp within the housing is disposed besidethe aperture in the front wall and substantially against the inside ofthe front wall of the housing, and said operating lever being of lighttransmitting material whereby the light from said lamp passes throughthe lever to the free end thereof.

9. A toggle switch for opening and closing electrical circuitscomprising an opaque housing, a switch operating lever mounted to pivotabout an axis inside said housing, the free end of the lever projectingthrough an aperture in one wall of the housing, the wall of said housingcontaining a window spaced from said aperture, said lever being of lighttransmitting material, and an electric lamp within the housingpositioned to transmit light through both said window and said lever.

10. A toggle switch for opening and closing electrical circuitscomprising an opaque housing, a switch operating lever mounted to pivotabout an axis inside said housing, the free end of the lever projectingthrough an aperture in one wall of the housing, the wall of said housingcontaining a second aperture, a rotatable closure for said secondaperture, said closure comprising a prism having one face parallel tothe axis of rotation of the closure and another face oblique to saidaxis, said lever being of light transmitting material, and an electriclamp within said housing positioned to transmit light through both ofsaid apertures.

11. A toggle switch for opening and closing electrical circuitscomprising an opaque housing, a switch operating lever mounted to pivotabout an axis inside said housing, the free end of the lever projectingthrough an aperture in one wall of the housing, said wall containing asecond aperture, an electric lamp within the housing and having aportion thereof projecting a short distance through said secondaperture, a transparent plate covering said second aperture and having ashallow recess in the inner face thereof to receive the projecting.portion of the lamp, an opaque shield in the bottom of the recesswhereby light passes from said lamp into the plate only through the sidewalls of the recess, and said lever being of light transmitting materialefiective to conduct light from said lamp through said first aperture.

12. A toggle switch for opening and closing electrical circuits,comprising a one piece opaque housing with an integral partitiondividing the interior thereof into a switch compartment and an adjoininglamp compartment, said housing having an opening between the twocompartments, a switch operating lever mounted to pivot about an axisinside the switch compartment, the free end of the lever projectingthrough an aperture in the outer wall of the housing, an electric lampmounted in said lamp compartment and adapted to shine through theopening between the compartments onto the part of said. lever inside theswitch compartment, said lever being of light transmitting materialwhereby it conducts light through said aperture to the free end of thelever.

13. A toggle switch for opening and closing electrical circuits,comprising a one piece opaque housing with an integral partitiondividing the 9 interior thereof into a switch compartment and anadjoining lamp compartment, said housing having an opening between thetwo compartments, a switch operating lever mounted to pivot about anaxis inside the switch compartment, the 5 free end of said leverprojecting through an aperture in the outer wall of the housing, anelongated electric lamp mounted in said lamp compartment and adapted toshine through the opening between the compartments onto the part of saidlever inside the switch compartment, the axis of said lamp beingtransverse to the pivotal axis of said lever and spaced laterallytherefrom, said lever being of light transmitting material whereby itconducts light through said aperture to the free end of the lever.

ELWIN W. SHERRARD.

10 REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS

